BOREALIS AF STUDY 2014.

Methods	Randomised, double‐blind, double‐dummy non‐inferiority clinical trial
Participants	3773 participants with AF documented by ECG and a history of previous stroke/TIA or non‐CNS systemic embolic events
Interventions	Idrabiotaparinux subcutaneous injection of 3 mg once a week for the first 7 weeks, thereafter followed by 2 mg once a week, except in participants with a creatinine clearance of 30 to 50 mL min (‐1) or aged ≥ 75 years who received 1.5 mg once a week after the first 7 weeks (n = 1886), or warfarin (dose‐adjusted to INR 2 to 3; n = 1887)
Outcomes	Primary efficacy outcome: composite of all fatal or non‐fatal strokes and systemic embolism Primary safety outcome: clinically relevant bleeding (major and clinically relevant non‐major bleeding) defined by ISTH‐criteria
Notes	Study sponsored by Sanofi‐Aventis
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomly assigned to treatment groups
Allocation concealment (selection bias)	Low risk	Participants were randomly assigned to treatment groups
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind, double‐dummy design
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinded central adjudication of all primary safety and efficacy outcomes
Incomplete outcome data (attrition bias) All outcomes	Low risk	Primary safety and efficacy outcome analysed in ITT population. Number of participants that discontinued during study and reasons reported
Selective reporting (reporting bias)	Low risk	All predefined efficacy and safety outcomes reported for ITT population
Other bias	High risk	Study was prematurely halted (3773 participants randomised of planned 9600 participants) by the sponsor for commercial/strategic reasons